Marine drilling



May 12, 1953 J. R. EVANS ET AL 78 MARINE DRILLING Filed April 25, 1946 3 shees sheet l V min Wafer Lei/el Invenfors John R. Evans Lloyd E. Elk/'ns Louis H. Kl/nz/ng y 1953 J. R. EVANS El AL 2,637,978

MARINE DRILLING Filed April 25, 1946 3 Sheets-Sheet 2 E 19 Z I lnvenfors:-

.Johh R. Evans Lloyd E. Elk/ns Louis H. Klinzing MARINE DRILLING 3 Sheets-Sheet 3 Filed April 25, 1946 0 n M Q? N mwmmfiw w 4 e mi w w nd w v WWW W v U/ v v W 2 a v v v M 0% Q r 3V w 6 H a v E w M Patented May 12, 1953 MARINE DRILLING ooh-n R. Ewan-s, Lloy E kins, and Lo is IL Klinziu Tulsa, Qkl

ration oi'iDelaware a., assl no rs to Stanolind Oil and Gas Company, Tulsa, .0k1a., a, coipo- Application ApriltZfi, 1946, ;Serial No. 664,891

8 Claims- 1 This invention relates to marine structures and to methods for their construction and erection, and more particularly to improvements in methods and structures for deep-water driIling.

Many of the methods and structures for drill ing underwater, which hav :been employed with some success in relatively shallow water, are not adaptable :to deep Water. Methods employing s bmer l dril ing arges and permanent docks constructed with piling cannot be practically adapted to drilling ,beneath any Waters which are as much as one hundred feet .or more in depth. The construction .,of caissons for drillin in waters of this depth is so enpehsiveas *to be prohibitive. Consequently there :is greatz eed .for

anefficlentand practical method qf dltil ing Wells in relatively deep Water in 5013161 to make the exploration and production-of toil reservoirs heneath these waters commercially practicable.-

. One of the present methods employed :is that of constructing a complete substructure which is adapted to be transported to the site and ran- .chcr-ed on the marine floor to support a plat form above the water level upon which a con- .rentional drilling derrick and rig is ,mounted ,for carrying out drilling operations To construct these substructures on dry .land or on ,barges and then lower them ,into the water upon completion is an extremely difficult .,.and expensive On ,alterhatiu-e method that has been disclosed by the art is that of building a structure from a plurality of similar .sectionsand assembling and welding these sections one upon the other in gradually deepening watenstarting from drylandand continuing to the locality Whenethe substructure is to be anchored, This ,method, however, requires towing that portion of the structure which is 'belowtheuwater level on skids extremely slow speeds and with the continued ri's: of tipping the structure, Furthermore, considerable expensiverunderwater work hydivers is required to anchor lthe'structure, ibis-permanent and cannot hedisassemhled, armature which desirable where, as in rexploratoryedrilling for oil a or gas, structure iis useful in @0119 locality for relatively short periods of time, and which locality may neverheprodueed.

Itis, therefore, .an-bbjecthof this inventionto provide a method 1of constructing rand -;-.erect.ing a portable .marinestructure ,ior use particularly in :deep wateratan desircd.location-:inasinrnler and more efficient manner than has heretofore been vpossible. It the ilzll'lihBI-Qbjfifli ,to provide an apparatus whichvmay Joe-so ,erecteuand particularly apparatus which sis adante'd ior mw er dri l nea d xplora n o thema ne floor on which it 85125). ltis yet a ;further oh ct to provide a ubstruc ure and a method ofere the such a substru tur whi h insures grea sta bility during erection and upon oompletion of t s r ture aga n t mo em nt du to Waves, winds, etc. An th r ob ect is t p ov a sub structure comprisi a plurality of sections which can he prefabric ed and then read-11 assembled and disassembled at the location where. the structure is tobe anchored, and further to provide'a method and apparatus for determining the elevation of the portions of the marine floor where the structure is to be anchored so that the .baseseotion can be fabricated in accordance with conditions :of the floor to insure optimum supportand stability for thecompleted structure. @therobjects and advantages will be apparent from the following description of my invention.

Our method of constructing and erecting a marine substructure particularly for deep-Water drilling is generally that of providing a guide means, such as a guide'post, extending upwardly from the marine floor toward the surface, preferably anchoring it at its base, and supporting itagainst sideWise movement or sway at the top, and threading on this guide means a plurality of apertured structural sections andsuperimposing one upon the other in such a manner ,as to form a unitary rigid structure. The number of sections required," of course, depends upon the depth o th Wa er ja i is Preferab that th mpl e sub r c u e extend ou of t e water to a point above the Waves. The" sections are ach similar and p e erably so constru ed a the as embled stru ture is o the skeleto ype Illa-vine ma eap rts or upr hts rigidly he d in spacedrelation by cross members and having a centrally disposed tube which slidably engages heeu de .means and thus coop a n with th same to provide also a support tor the structure against sideuzise movement ,oiysway. We jurther har hr vid dinterlockingmean on-the ad a ent individual sections so as to further increase the strength and stability of our substructure, even thou h, being of he skeleton typ itl i r a minimum resistance to wav action e.

t' rther a sure/neetofstability, particularly duri evereution, wesupuor the guide po a a least two vertically spa ed points n ar he surwhen threadin lhefitructural sec,- 'ostduringerection the post is conv. .y I upp r ed .hy de chins fi st the. pport. ithreadiusrthe .se otidn,;-past hils s pport, at

taching it again, and then detaching the second support.

As yet a further assurance of stability of our structure, we ascertain the relative elevation of the firm portions of the marine bed upon which the uprights rest and are anchored, and then construct the base section so that it will rest firmly thereon with its axis perpendicular to the surface of the water. To determine this relative elevation, we utilize as a gauge a support for a number of gauge bars which can be threaded on the guide means and lowered to the marine floor. The gauge bars are held in the same relative position in a vertical plane as that of the upright segments of the base section. The gauge bars indicate the relative elevation of the loci for the uprights when they strike solid portions cross members 1. Centrally disposed within the area defined by the uprights 5 is a tube 8 rigidly supported by the uprights through radial braces 9 (Figure 3). Within the tube 8 is disposed a vertical guide means or column [0, preferably tubular, anchored on the marine floor at its base II and supported against lateral movement or sway preferably near the top by buoyant means or, for example, by two spaced supports or detachable split collars l2 and 13 (Figure 6). Guy wires I 4 and I 5, which are anchored by naval anchors I 8 (only one shown) at spaced points substantially removed from the base of the substructure, are secured to these detachable split of the marine floor. In order to insure that the base section assumes the same position as the gauge, it is preferable that they each be restrained from relative rotation with respect to the guide means as they are lowered.

Our marine structure can be particularly adapted to underwater drilling operations by using as the guide means means including a guide and conduit, as for example, a tube, or a plurality of tubes trussed together, which, when supported by the skeleton structure, may serve as the conducting string or strings through which the drill string operates and the well is produced. Where this is the intended result, the guide and conduit means may in some cases only be temporarily anchored until the skeleton structure is complete and in place.

The above features of this invention and others will be better understood from the following description of a preferred embodiment when read in connection with the accompanying drawings wherein like numerals indicate similar parts and wherein:

Figure 1 is a diagrammatic elevation of a marine substructure in accordance with this invention, particularly for use in supporting an oilwell derrick and complete drilling rig;

Figure 2 is a fragmentary elevation partially in section showing particularly the base section of our marine substructure and the means for anchoring it to the marine floor;

Figure 3 is a diagrammatic plan taken along the 3-3 of Figure 2;

Figure 4 is a section taken along the line 4-4 of Figure 3;

Figure 5 is a fragmentary elevation showing another modification for supporting the base section of Figure 2;

Figure 6 is an elevation partly in section of a guide means for our marine substructure during the first stages of construction and our apparatus for determining variations in the elevation of the marine floor;

Figure '7 is a fragmentary view of the apparatus shown in Figure 6;

Figure 8 is a diagrammatic elevation of an alternative embodiment of a guide and conduit means.

Our preferred substructure for oil-well drilling is a skeleton structure I of frustro-pyrarnidal shape having mounted thereon a conventional oil-well derrick 2 supported on a deck 3 from which oil-well drilling operations can be conducted in the marine floor 4 beneath the substructure. The substructure as shown comprises four main supporting uprights 5, preferably hollow or tubular, which are rigidly held by braces, such as horizontal cross members 6 and diagonal collars I2 and I3, respectively.

The skeleton structure I is formed of a plurality of similar independent frustro-pyramidal sections of skeleton formation, as for example, base section 20, the next adjacent section 2 l, etc., which are superimposed one upon the other and each including tubular uprights 22, a vertical tube 23, the horizontal cross members 8, diagonal cross members 1, and radial braces 9. The tubular uprights 22 and vertical tube 23 of each sec tion are segments making up the continuous main supporting uprights 5 and centrally disposed tube 8, respectively. Each of these sections is interlocked with respect to each other by a dowel 24 and a socket 25 on the abutting ends of the segments of the tubular uprights 22 (Figure 4). This interlocking of each section adds to the rigidity of the entire structure against lateral movement or sway. In some instances, interlocking against vertical movement or displacement may be obtained by a latch, such as a. pawl and stop, but in general the weight of the sections is sufficient.

In erecting the marine substructure of Figure l, the vertical column I0 is lowered to the marine floor at the desired location and temporarily anchored by prongs or teeth 26 at the base thereof which tend to penetrate mud or sand on the marine floor and secure a firm footing for the column. The upper end of the column, which preferably extends above the water level, is then supported against lateral movement or sway by the guy wires [4 and IS. The collars to which the guy wires are attached are secured to the column ID at points vertically spaced a distance at least as great as the height of any one section fOr reasons hereinafter set forth. The vertical column may be permanently anchored to the main floor with hydraulic cement as by a cement plug 28 reinforced with a tube 29 or drill rod extending through a part or all of the column ll and into a. hole 30 beneath the column. This hole can readily be made by passing a rotary drill .down through the column.

By using a tubular column we not only have provided guiding means, but also have provided conduit means permitting the use of this advantageous method of anchoring, as well as a conducting string through which the drilling may be accomplished and the well produced in those instances where the substructure is used for drilling wells. In these cases in which the substructure is used for drilling wells, the well may be drilled from any position within the confines of the substructure but preferably the reinforcing tube 29 used in anchoring may be selected of a sufiiciently large diameter to receive the drill bit and thus serve as the well casing. In some cases wherein the substructure is used for drilling, the column I!) alone may serve as the casing, either anchored in cement or merely anchored by the 44, 45, and 46. A vertical column or guide post of this type may also include, where it is desired to drill a plurality of wells, as an integral part thereof, a plurality of pipes 41 suitably supported by the braces 44, which may serve as conductor strings for a number of different Wells to be drilled from the structure. In this embodiment the central tube 42 may be permanently anchored with cement as described above.

The above description of a preferred example of our marine substructure and method of constructing and erecting the same is given by way of illustration and many modifications and variations will occur to those skilled in the art. Therefore, no limitations are intended by the above description except as are contained in the following claims.

We claim:

1. A marine substructure comprising a vertical column, means for anchoring said vertica1 column in the marine floor, means supporting said column against lateral movement or sway, and a frustro-pyramidal skeleton structure including supporting uprights and a centrally disposed axial tube disposed around said vertical column, said tube and said uprights being held in rigid spaced relation by braces.

2. A marine substructure comprising a guide column, means for anchoring said guide column in the marine floor, means for supporting said guide column in a substantially vertical position, and a plurality of structural sections having a centrally disposed aperture threaded on said guide column and superimposed one upon the other, all said sections forming a rigid elongated structure.

3. The marine substructure of claim 2 wherein said means supporting said guide column comprises at least two sets of guy wires detachably secured at vertically spaced points to said guide column at one end and anchored in the marine floor at the other end.

4. A marine substructure for Well drilling comprising a plurality of structural sections of skeleton formation superimposed one upon the other, each of said sections including hollow uprights and an axial tube, said uprights and said tube being held in rigid spaced relation by braces and said uprights and said tube of each of said sections being in substantial alignment, forming thereby continuous hollow uprights and a continuous tube extending from the marine floor to above the water level, a vertical tubular column disposed within said continuous tube and extending from the marine floor to a point above the top of said tube, means for anchoring said column in the marine floor, means to support said column against lateral movement. and means disposed throughout each of said continuous hollow uprights and in said marine floor for anchoring each of said sections relative to said marine floor.

5. The marine substructure according to claim 2 which comprises cooperating surfaces on said guide column and the centrally disposed aperture of said structural section adapted to prevent relative rotation between said guide column and said structural section.

6. A marine substructure comprising a plurality of superimposed rigid frustro-pyramidal sections of non-buoyant construction, each of said sections including a centrally disposed tube and non-coaxial upright supports, said centrally disposed tube being held in rigid spaced relation to said uprights by braces and all of said superimposed sections forming together a rigid elongated structure having a continuous centrally disposed tube in spaced relation to the uprights of said structure, and a tubular column disposed within said central tube and extending from the marine floor to above the upper end of said elongated structure.

7. A frustro-pyramidal section for a marine substructure comprising a centrally disposed guide tube, upright supports held in spaced relation to said tube by braces, the length of the component of said upright supports parallel to the axis of said tube being substantially equal, interlocking dowel means at the ends of said upright supports to connect to the ends of similar supports of other frustro-pyramidal sections, and spline means in said tube adapted to cooperate with a guide member to orient said section, whereby said upright supports will be aligned with and will engage supports of other frustropyramidal sections when they are lowered on said guide member and whereby a minimum of underwater work by divers is required to assemble a number of such sections and to erect a marine substructure.

8. In the process of erecting a marine substructure having a multiplicity of spaced supporting uprights on an uneven marine floor, the steps of setting on said floor a guide column which extends above the water level, supporting said guide column against lateral movement, threading onto said guide column a gauge support having gauge bars in spaced relation and oriented to correspond to the proposed position of said uprights, said gauge bars being movable vertically relative to said gauge support, lowering the gauge support until the vertical position of said gauge bars corresponds to the elevation of the floor at the proposed position of said uprights, and retrieving said gauge support whereby said substructure can be prefabricated to stand erect on said uneven marine floor before said substructure is lowered to said floor.

JOHN R. EVANS. LLOYD E. ELKINS. LOUIS H. KLINZING.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 36,512 Bois Sept. 23, 1862 178,438 Hill June 6, 1876 510,264 Kash Dec. 5, 1893 1,811,761 Roberts June 23, 1931 1,998,803 Collins Apr. 23, 1935 2,077,044 Grace et al Apr. 13, 1937 2,102,555 Dyer Dec, 14, 1937 2,236,682 Gross Apr. 1, 1941 

